As it has become commonplace to incorporate cameras into portable electronic devices, it has started to become commonplace to include optical image stabilization (OIS) in those devices to improve the quality of the images captured with those cameras. However, as familiar to those skilled in the art, the addition of such features as OIS, automated color correction, automated light level control, etc., often increases the amount of electric power consumed from what is usually a limited source of electric power (e.g., a battery) during the use of such devices to capture images.
By way of example, the inclusion of OIS often entails the addition of multiple voice coil motor (VCM) actuators to move about at least a portion of a camera in response to relatively small movements arising from unsteadiness on the part of a person physically supporting the portable electronic device to capture an image. Multiple VCM actuators are usually employed to counter relatively small horizontal and vertical movements that arise from such unsteadiness, and not from a deliberate movement for image panning, etc. Unfortunately, although VCM actuators are quite capable of effecting relatively small movements of at least a portion of a camera to counter relatively small movements arising from unsteadiness in the physical support of a portable electronic device, such use of VCM actuators does have drawbacks.
VCM actuators have no ability to hold an object in a chosen position unless continuously provided with electric power such that an object either moved to a chosen position or held there by a VCM actuator is able to move freely once electric power is no longer provided. As a result, some implementations of OIS include the use of springs to assist VCM actuators in holding at least a portion of a camera at a location to which a VCM actuator has been used to move it. Unfortunately, aside from adding undesirably to the quantity and weight of parts employed in implementing OIS, every mechanical spring has a resonance frequency at which it can be caused to begin vibrating such that electric power may still be need to be applied to a VCM actuator on a frequent basis to counter such a vibration.
Further, detecting the position of an object moved by a VCM actuator typically requires a separate sensor component. For implementations of OIS, this typically results in the need to add two or more sensor components to detect the current position of at least a portion of a camera moved about by VCM actuators, thereby again adding undesirably to the quantity and weight of parts employed in implementing OIS.